Flashcards in Endovascular Ablation Techniques with Ambulatory Phlebectomy for Varicose Veins Deck (52):
Failure to treat proximal incompetence results in vein recurrence.
Endoluminal radiofrequency or infrared laser energy can effectively seal and eliminate abnormal saphenous veins.
Ambulatory phlebectomy may be performed on distal or branch varicose veins in combination with endovenous techniques.
Tumescent anaesthesia is not required for ambulatory phlebectomy or endoluminal radiofrequency or laser closure.
F Tumescent anaesthesia is necessary.
For maximal improvement in abnormal venous haemodynamics and resolution of symptoms, complete removal of the great saphenous vein from the saphenofemoral junction (SFJ) to the knee is required after ligating the SFJ.
Patients cannot return to work for up to 6 weeks after endovenous techniques.
F 1-72 hrs.
Sclerotherapy can be used as an adjunctive treatment to eliminate branch varicosities that don’t resolve with closure of the great saphenous vein alone.
Doppler units utilise frequencies for 4-5 MHz for examining superficial vessels (1-2 cm below the skin), while deeper vessels require a higher frequency of 8-10MHz.
F 8-10 MHz for superficial, 4-5 MHz for deep.
Using Doppler ultrasound, a long flow sound is audible when valves are incompetent.
Doppler examination of the superficial venous system should be performed when the patient is lying down.
F Standing or sitting gravitational hydrostatic pressure enhances vol and velocity of flow.
Using a Doppler ultrasound, flow that is heard during proximal compression or immediately after the release of distal compression is normal.
F This is retrograde flow – a sign of incompetent valves.
Duplex ultrasound consists of a dual-mode device that allows a timed pulse echo to be superimposed with the continuous-wave Doppler.
Doppler shows venous reflux more precisely than a Duplex ultrasound.
F Reflux shown visually and more precisely with Duplex.
The site of origin of reflux can be pinpointed with Duplex ultrasound.
Retrograde flow of duration >1second is considered pathologic reflux, and reflux that lasts >2 seconds is haemodynamically significant.
Once incompetence of the great saphenous vein has been demonstrated with reverse flow, the patient is a candidate for an endovenous ablation technique.
To shrink vessels, endovenous placement is used to direct radiofrequency energy to heat a catheter which then heat damages vein walls.
All endovenous techniques heat the vessel at an optimal temperature of 70-90 degrees Celsius.
F 120 degrees or beyond.
With radiofrequency techniques, the temperature increase remains localised in a narrow rim around the active electrode.
Tumescent anaesthesia and immediate ambulation are not important factors in minimising the side effects of radiofrequency closure.
F These are the most important factors.
It is advisable to limit radiofrequency treatment to the great saphenous vein to below the knee to minimise the risk of paraesthesia resulting from injury to the saphenous nerve.
F Above the knee.
With radiofrequency ablation, a 7cm long metal core is heated to 120 degrees and allowed to transmit head to the treated vessel for 20 seconds, which shrinks a vein 7cm at a time.
Endovascular radiofrequency ablation techniques have higher rates of side effects of DVT and nerve injury compared to traditional ligation and stripping.
With endovascular radiofrequency ablation, results observed at 6 months are indicative of the long-term results.
The superior epigastric vein is typically ablated using endovascular techniques.
F Endovenous techniques are designed to preserve this vein.
Ambulatory phlebectomy cannot be used in combination with radiofrequency endovenous ablation techniques.
Regarding radiofrequency closure with ambulatory phlebectomy, most physicians use the technique of duplex-guided puncture and cannulation.
The amount of tumescent anaesthesia fluid used for ambulatory phlebectomy ranges from 1L – 1.2L.
F 500-800mL with typical lignocaine dose of 4-8mg/kg.
The incisions made during ambulatory phlebectomy are sutured closed following the procedure.
F Kept open to allow for anaesthesia drainage, minimising swelling and bruising
There is no need for compression following radiofrequency closure with ambulatory phlebectomy.
F Compression bandage applied immed after procedure and removed next day.
Patients with reflux in the great or small saphenous vein are candidates for the technique of closure using single puncture under duplex guidance.
For the technique of closure using single puncture under duplex guidance, it’s best if the vein size does not exceed 1mm.
For the technique of closure using single puncture under duplex guidance, the entry point is usually just above or below the knee along the course of the great saphenous vein.
For the technique of closure using single puncture under duplex guidance, it is important that the patient experiences no pain during cannulation.
T The perception of pain will cause immediate and rapid contraction of the saphenous vein.
For the technique of closure using single puncture under duplex guidance, monitoring of the anaesthesia injection is not required.
F It’s essential.
For the technique of closure using single puncture under duplex guidance, tumescent anaesthesia is injected into the perivenous space.
With the technique of closure using single puncture under duplex guidance, the starting temperature when the catheter is in position should be 37 degrees Celsius.
F It should be 25-28 degrees if tumescent anaesthesia has been properly placed.
At the conclusion of the procedure of closure using single puncture under duplex guidance, the duplex ultrasound of the saphenofemoral junction should reveal no flow except for the superficial epigastric emptying into the common femoral vein.
At the conclusion of the technique of closure using single puncture under duplex guidance, the greater saphenous vein should be less echogenic with thinner-appearing walls.
F More echogenic, thicker-appearing walls.
Class 2 compression hosiery should be worn for 3 days with the percutaneous closure technique.
Class 2 compression hosiery should be worn for 14 days with the closure plus phlebectomy technique.
F 7 days.
Anaesthesia of the treated portion of the leg may persist for 8-24 hours following endovenous radiofrequency ablation with tumescent anaesthesia.
Symptom relief following endovenous radiofrequency ablation is usually not seen until 6 weeks after the procedure.
F Usually rapid (some within 3 days).
Clinical improvement in the appearance of varicosities following endovenous radiofrequency ablation is typically seen within 6 weeks.
Destruction of the great saphenous vein with laser is a function of thermal destruction.
Using endovenous laser ablation, the incidence of postoperative pain and ecchymosis is highest in water-dependent wavelength (1320nm).
F Haemoglobin-dependent wavelengths (810, 940, 980, 1064nm).
Pulsed 810nm diode laser treatment decreases risk for perforation of the vein compared to continuous treatment.
F Increased risk with pulsed treatment.
Regarding endovascular laser ablation, longer wavelengths (eg. 940nm) penetrate deeper into the vein wall with resulting increased efficacy.
When compared to the 940nm diode laser, the 1320nm Nd:YAG laser causes fewer side effects in the endovenous treatment of the great saphenous vein.
Endoluminal laser ablation utilises a helium-neon aiming beam that is continuously illuminated to ensure that the laser fibre is in the superficial venous system.
Lymphocoele is an very uncommon adverse event of endovenous ablation.
F Most common.